Clinical versus instrumented knee testing on autopsy specimens

Area of Science:

• Orthopedics
• Biomechanical Engineering
• Sports Medicine

Background:

• Accurate assessment of anteroposterior knee laxity is crucial for diagnosing anterior cruciate ligament (ACL) injuries.
• Instrumented devices like the Genucom Knee Analysis System and Knee Signature System (KSS) aim to provide objective laxity measurements.
• Previous studies have explored the utility of these devices, but their clinical reliability remains a subject of investigation.

Purpose of the Study:

• To compare the accuracy, reliability, and reproducibility of the Genucom and KSS for anteroposterior knee laxity evaluation.
• To compare the performance of these instrumented devices against a subjective clinical examination.

Main Methods:

• Specimens with and without ACL deficiency were tested using the Genucom and KSS to compare relative laxity changes.
• A clinical study involved ten patients undergoing Lachman and drawer tests performed by two independent examiners using the Genucom, KSS, and subjective clinical assessment.

Main Results:

• Both devices detected relative laxity changes but differed in absolute values.
• The Genucom exhibited interexaminer variability during Lachman testing.
• The subjective clinical examination demonstrated higher reliability than both the Genucom and KSS for both Lachman and drawer tests.
• High intraexaminer variability was observed for both Genucom (±4.2 mm) and KSS (±2.8 mm) at 95% confidence limits.

Conclusions:

• The Genucom and KSS demonstrate significant variability, questioning their accuracy and reproducibility in clinical settings.
• Subjective clinical examination is currently more reliable for assessing knee laxity compared to the evaluated instrumented devices.
• Further research is needed to improve the reliability and accuracy of instrumented knee laxity assessment systems.